Will female Democrats favor Webb — currently in his third marriage and the author of what some might consider a sexist novel — over Hillary Clinton? Not likely.

Will African-Americans favor Webb — so proud of his Scotch-Irish heritage — over the wife of “our first black president”? Not likely.

Will white southern Democrats favor Webb? Arguably. But he’s going to be running as a left-wing populist, and many white southern Democrats remain moderate.

Will wealthy Democrats back Webb? No. They can forgive populist rhetoric if they know it’s insincere, but they can’t be sure that Webb doesn’t mean what he says.

Suppose, however, that Hillary Clinton’s campaign implodes. In this scenario, we can expect Elizabeth Warren to enter. Warren would then become the favored candidate of females, radicals, and many other leftists. Even the wealthy would probably favor Warren over Webb, since she comes across as less than sincere.

If the scenario I’ve just described sounds familiar to old-timers, it’s because it resembles what happened in 1968. Going into the campaign season, President Johnson was the heavy favorite (as Clinton is now) but many on the left were urging Robert Kennedy to run (as they are now urging Warren to do).

Kennedy lacked the guts to challenge LBJ, but Eugene McCarthy was up for the fight. Though McCarthy didn’t defeat Johnson in the New Hampshire primary, he did well enough to cause Kennedy to enter the race. Soon thereafter, Johnson announced that he would neither seek nor accept his party’s nomination.

I would expect Warren to follow Kenney’s example and enter the race if Clinton were to withdraw or falter in 2016. Warren’s challenge will resemble Kennedy’s in terms of ideology, though she will be nothing like the campaign trail dynamo Kennedy was in 1968.

With Johnson out of the race and with two left-wing antiwar candidates fighting for the nomination, Vice President Hubert Humphrey announced his candidacy and attempted to rally the party establishment around him. Would Joe Biden do the same in 2016? I believe he would.

Whether Webb finds himself in a two-way race against Clinton, a two-way race against Warren, or a three-way race against Warren and Clinton or Biden, I consider him very unlikely to prevail.

I don’t deny that Clinton, Warren, and Biden all have serious deficiencies as campaigners. Webb, though he hasn’t shown himself to be a great campaigner, possesses the authenticity Clinton and Warren lack, and is not a bumbling windbag like Talkin’ Joe Biden.

But the logic of the race in a party where identity counts for so much is badly stacked against Webb.